Reed Switch and Electromagnet
by TheShadowArchitect
Summary: I found the concept of modulating a sound frequency into an electric signal strong enough to pace someone fishy. Especially since the only power in that entire system was the cell phone battery. Here's how I would have saved Vasquez.


They pulled the secretary of defense out of the car and laid him on the concrete, the seconds suddenly ticking by a lot more urgently than they had even moments before. Cage leaned down to check for a pulse. Nothing. No breathing either, which was probably what the hackers had been going for. She started CPR.

"How did we not know this guy had a pacemaker?" Mac asked. "Matty read his entire file." Not that it mattered now, even if it felt good to express the frustration. If he had known he might have done something to shield the device before the guy was lying pulseless in front of him.

"Vasquez was eyeing the road to the presidency." Cage explained. "So its not a surprise he tried to hide it." She leaned down to see if there was any change in condition. Still pulseless and without breath. "Listen, Mac, if his pacemaker isn't working, CPR's only going to hold him for so long." She said. "We have to get him to a hospital. Now."

"I know, I…" Mac said, looking around to see if anything in the warehouse sparked any inspiration. "Wait- wait, hold up." Mac said, almost pushing her off the SecDef's chest.

"What are you- Mac! If I stop CPR he dies regardless!"

"I know, I just need to figure out if they turned the pacer off completely or if they just reprogrammed it." Mac said urgently. Cage looked distrustful.

"Okay, five seconds." She said warily, pulling off his chest just enough that Mac had some room to work. He leaned down to listen carefully against the man's chest. Inside he heard a weak wobbling sound he couldn't place. Thank god, the pacemaker was still working. Not well, and certainly not in a way compatible with life, but they hadn't turned the thing off completely, which was something he could work with.

"Okay, start compressions again, I know what happened." Cage looked confused, but gratefully restarted CPR.

"And?" She looked at him expectantly. Mac had already run over to the car.

"When they hacked his pacemaker, they must have reprogrammed it to pace way over the safe threshold." He explained as he pried a speaker from the car's stereo. "His heart's getting paced so fast it's not getting time to fill with blood in between beats, which means its not actually pumping anything."

"Crap."

"Tell me about it." He said.

"Can you fix it?" She asked.

"I might be able to buy him some time."

 _When talking about devices you don't want to crap out on you, the pacemaker is pretty far up on the list. And, when you're dealing with electricity and the human body, there's a lot that could potentially go wrong. Fortunately, for being cardiologists, the inventors weren't overly riddled with hubris when they designed them- all modern pacemakers have a failsafe function called a Reed Switch in the case that the normal programming starts causing problems._

 _It's a simple concept, really. If the tiny computer driving the pacer senses the presence of a strong enough magnetic field, it resets to a hardwired number of paces per minute. Nothing smart- it can't sense what the heart is doing to prevent potentially deadly problems in itself or react to changing conditions, but it forces the machine to keep the heart paced at a rate minimally compatible with life until someone can fix whatever's causing the problem._

Mac brought over the speaker and quickly got to work dismantling it as Cage continued CPR, looking at him quizzically.

 _All I need is a magnet strong enough to trip the Reed Switch until we can get Vasquez to a hospital where someone with an interrogator- a computer capable of communicating directly with the pacer- can override whatever code the hackers put on it and reset it to its original settings. Usually, those magnets are static, but since I don't have a strong enough static magnet readily available, I'm hoping an electromagnet will work just as well to generate the field I need. All speakers run on electromagnets, relying on them to push against a static magnet which moves a flexible piece of plastic or cloth that generates waves in the air that we can then interpret as sound. The static magnet from a car speaker probably isn't gonna cut it, but I'm borrowing the electromagnet and hopefully by giving it a steady DC power supply, I can mimic one that will work._

Mac pulled the tiny electromagnet component from the speaker and stripped the ends of the wire coil coming off it. Now he needed a battery….

Anyone with a classic car in this level of condition would keep a repair kit handy with a flashlight in it. Mac checked under the back seats. Nothing. He hoped it wasn't in the trunk. Despite being able to hotwire the car quickly, picking the lock on the trunk would take more time than he had.

The glove compartment, fortunately, held the flashlight. A nice big old one that could double as a weapon, with a miniature incandescent bulb that needed two D batteries to run. Mac couldn't have asked for better. He duct taped the ends of one of the batteries to the stripped ends of the wire, and set the contraption over the lump on Vasquez's chest.

"Cage, I'm gonna have you stop for a second so I can check a pulse." Mac said. Cage pulled her hands away as Mac set his finger's against the SecDef's carotid artery. There was a pulse. Cage's hands were still in formation to continue compressions.

"Well?" She asked.

"We're good." Mac said, taping his electromagnet down to the man's chest and pocketing the second battery. He couldn't risk draining the one powering the electromagnet before Vasquez got to a hospital. Vasquez groaned.

"Stay still, Sir." Mac warned, pulling the man's hands away from exploring the contraption on his chest. "You don't want to touch that."


End file.
